1. Field of the Invention
The present invention relates to a manufacturing technology of liquid crystal display device, especially to a method of splicing polarized films.
2. Description of the Related Art
Liquid crystal display device (LCD) has been widely used in all kinds of electronic products. Presently a liquid crystal display device mainly includes two transparent substrates, a liquid crystal layer mounted between the substrates and two polarized films respectively mounted on outer surfaces of the substrates.
The polarized films are important components in a liquid crystal display device. When lights pass through one of the polarized films, the lights become polarized lights in the same polarization direction as the polarization axis of the polarized film. Liquid crystal molecules of the liquid crystal layer are controlled by an external electric filed and accordingly twist, thereby controlling whether the polarized lights can pass through the other polarized film so as to change the brightness of each pixel in the liquid crystal display device.
In general, polarized film suppliers provide polarized films in rolls for sale. Polarized-film rolls in the present market are limited in width (lower than 2 meters) due to the limitation of the manufacturing equipments, thus, if a manufacturer tends to produce liquid crystal display panels having widths larger than the width of the purchased polarized films (for example, larger than 2 meters), it is necessary for the manufacturer to splice the polarized films.
Thus, manufacturers of thin-film transistor LCD all use a polarized-film splicing technology to manufacture products with larger sized liquid crystal display devices. With reference to FIG. 1, a first polarized film 80 firstly is attached to a surface of a liquid crystal cell 9, and then a second polarized film 81 is aligned with an edge of the first polarized film 80 and attached to the surface of the liquid crystal cell 9. However, the splicing accuracy of the present splicing technology is limited (0.3 micro-meters approximately), and there is a certain interval 800 between the spliced polarized films 80, 81, and thereby causing the liquid crystal display device to have light leakage at the position of the interval 800 such that the pixels corresponding to the position of the interval 800 cannot display correctly.
Therefore, it is necessary to provide a method of splicing polarized films to overcome the problems existing in the conventional technology.